In a Frequency Division Duplexing (FDD) communications system, a base station of a cell usually needs to provide a service to multiple UEs connected to the cell; however, due to limited communication resources, the base station needs to provide a service preferentially to a few UEs having better channel quality according to channel quality of UEs. Specifically, the base station transmits a downlink reference signal, and UE calculates downlink channel quality according to the received downlink reference signal, and feeds back CSI to the base station according to the downlink channel quality. After receiving the CSI reported by each UE, the base station selects, according to a preset scheduling policy, several UEs from all UEs connected to the cell, so that the base station provides a service to the several UEs.
When a large quantity of UEs exist in the cell, the base station can provide a service only to a limited quantity of UEs of the large quantity of UEs; however, because all UEs need to report CSI to the base station, unscheduled UEs report CSI and therefore occupy a large number of uplink communication resources. Therefore, in the prior art, to reduce an overhead for CSI feedback, the base station may broadcast one threshold to the UEs, and only UE whose channel quality exceeds the threshold feeds back CSI to the base station. However, because channel quality of UEs at edges of the cell is usually relatively poor and is always less than the threshold broadcast by the base station, it is always difficult for the base station to schedule these UEs, and these UEs cannot use a service provided by the base station, resulting in that performance of the UEs at the edges of the cell is not high.